SAN DIEGO – With one swing, Orioles first baseman Chris Davis erased the disappointment of his previous three at-bats Wednesday at Petco Park.

Davis had already struck out twice and stranded four baserunners — including three in scoring position — when he stepped to the plate in the eighth inning of a tie game against the San Diego Padres.

Wasting no time, he blasted left-handed reliever Colt Hynes’ first pitch deep into the right-center field seats. The three-run homer started a string of seven unanswered runs for the Orioles in a 10-3 win before an announced 21,206.

Davis’ majors-leading 41st homer of the season also elicited collective awe from the seating bowl, traveling an estimated 453 feet, tied for the second-longest home run in the 10-year history of Petco Park.

“I don’t know if it was the longest one I’ve hit,” Davis said. “It was one of the longer ones. It helped that the wind was blowing out a little. But in that situation, I’m looking for a pitch out over the plate that I can drive and try and be aggressive. I think I had some pitches earlier in the game I thought I could hit, but I was behind them and underneath them. So to get that pitch early and put a good swing on it, it felt good.”

While the hulking Davis has become known for his moon-shot homers, his longball Wednesday was one that won’t be forgotten quickly inside the Orioles clubhouse.

“That’s a bomb,” said Orioles center fielder and San Diego native Adam Jones, who was 7-for-9 in his two-game return to his hometown. “Anybody can hit a home run down by five, but the situation, the inning, and it was big. That was the game-winning home run.”

Said manager Buck Showalter: “It was loud. But he’s not picking on anybody. The thing about Chris is he’s so lethal. He may have some bad at-bats, but you never think he’s not a swing away from really doing something good for you.”

With the win, the Orioles (63-51) swept the two-game series in San Diego — their first stop on a three-city, eight-game West Coast trip that continues with stops in San Francisco and Arizona.

“Any time you’ve got to fly across the country and play two right off the bat, it’s going to be an obstacle,” Davis said. “But we did well earlier in the year handling the West Coast trip, and we’ve started out here on the right foot.”

Earlier in Wednesday's game, the Orioles didn’t take full advantage of three Padres errors, stranding a runner at third with no outs in the fourth and leaving the bases loaded in the fifth.

The Orioles were 2-for-8 with runners in scoring position before Davis’ home run, which came on a 79-mph slider and extended his major league-leading RBI total to 106.

Right-hander Miguel Gonzalez held the Padres (52-62) scoreless through his first five innings, limiting San Diego to three hits in that span. But Padres second baseman Jedd Gyorko blasted a three-run homer in the sixth off Gonzalez to tie the game at 3-3.

Keeping the Padres off-balance early with his split-fingered fastball, Gonzalez had six strikeouts through his first 3 1/3 innings, including one span in which the stuck out four straight.

After allowing a leadoff double to Alexi Amarista in the second inning, Gonzalez retired 10 straight and 12 of 13 before issuing a leadoff walk in the sixth to Chris Denorfia. Two batters later, Yonder Alonso followed with a broken-bat single and then Gyorko took a 2-0 fastball over the wall in left-center.

“When you’re going five strong innings and you’re going into the sixth inning and a guy gets a broken-bat base hit, it’s a little frustrating when that happens,” Gonzalez said. “But I kept my team in the game, and we played a good game overall.”

Despite not getting a decision, Gonzalez showed improvement from back-to-back rough outings. He had allowed 15 runs — 10 of them earned — in his previous two starts covering 8 1/3 innings.

“You could tell early on he was carrying an extra little finish in his fastball,” Showalter said.

Shortstop J.J. Hardy, who matched a season high with three RBIs, put the Orioles up 1-0 in the second inning with his 19th homer of the season, taking a 0-2 fastball off the second deck of seats of the Western Metal Supply Co. building in left.

Manny Machado reached base to open the fourth when first-base umpire Angel Hernandez ruled that Alonso’s foot came off the bag, resulting in a throwing error charged to Gyorko. Jones, followed with a single up the middle, and Amarista’s throw to third skipped into the Orioles dugout, allowing Machado to score and putting Jones at third.

But the Orioles couldn’t break the game open, as Padres lefty Eric Stults retired the next three hitters, including strikeouts of Davis and Hardy.

The Orioles added a run in the fifth on Machado’s bases-loaded RBI single with one out to make the score 3-0, but they would strand the bases loaded with Jones striking out and Davis flying out to center.

Davis ultimately redeemed himself with his mammoth blast off Hynes.

“I felt good the last couple of games,” Davis said. “I felt comfortable in the box. I just haven’t had much to show for it. … To go out there today and just have two awful at bats and leave guys on in the third at-bat, especially in a tight game, to get the homer it was huge, not just for me, but for the whole team.”

After Davis’ homer, the Orioles added another run in the eighth on Brian Roberts’ sacrifice fly. The Orioles tacked on three more in the ninth, capped by Hardy’s two-out, two-run single.

“They’re all tough,” Showalter said of the win. “It’s a good start to a challenging road trip. … The guys feel good about themselves for an off day [Thursday]. We’ll see what San Francisco has in store for us.”

SAN DIEGO -- Thanks to a double switch that Orioles manager Buck Showalter made in the bottom of the eighth inning of Wednesday’s victory over the San Diego Padres, right-handed reliever Darren O’Day was slated to bat eighth in the ninth inning.